### Breaking News # Mechanics Rotational dynamics online mcqs quiz

Rotational dynamics2 quiz..

1) For counter clock wise rotation angular displacement is

1 point

Negative

Positive

Some times positive some times negative

All of them

None of them

2) 3 radian is equal to

1 point

90 degree

180 degree

360 degree

114.6 degree

None

3) If a particle moves in a circle of radius r with uniform angular velocity w then the angle between radius r and linear velocity is

1 point

90 degree

180 degree

60 degree

45 degree

4) When a wheel. 1m in diameter, makes 30 rev/min, the linear speed of point on its rim in m/s is

1 point

pie

pie/2

130 pie

60 pie

5) A body is executing uniform circular motion. Its angular acceleration is

1 point

Zero

Proportional to angular velocity

Proportional to angular displacement

None of these

6) Law of conservation states that if No ----- acts on a system, the total angular momentum of the system remains constant

1 point

External force

External couple

External torque

All of these.

7) If a rotating body is moving anti-clock wise, the direction of angular velocity is

1 point

towards the centre

away from centre

Prependicular to both radius and linear velocity

along the linear the velocity

8) The product of moment of inertia and angular velocity of a rotating body is equal to ----

1 point

linear momentum

linear velocity

angular momentum

angular velocity

9) The rate of change of angular momentum is equal to

1 point

force

impulse

angular acceleration

none of these

10) If a body is moving with uniform angular velocity then torque acting on the body is ------

1 point

positive

negative

zero

none of them

11) Moment of inertia plays the same role in angular motion as ------ plays in linear motion

1 point

linear velocity

impulse

mass

torque

12) Angular momentum has the same unit as:

1 point

inpulse x distance

linear momentum x time

work x frequency

power x time

13) the moment of momentum is called

1 point

torque

couple

impulse

angular momentum

14) The moment of inertia of a fly wheel is 4 kgm^2. A torque 0f 10 Nm is acting on it. The angular acceleration in it is ----

1 point

zero

15) A particle is revolving in a circle of radius "r", its displacement after completing half the revolution will be

1 point

pie (r)

2 r

2 (pie) r

r/2

16) Calculate the rotational inertia of a meter stick, with mass 0.56 kg about an axis perpendicular to the stick and located at 20-cm marks

1 point

964 kg m^2

0.0964 kg m^2

96 kg m^2

none of these

17) What is the angular speed hour hand of a watch

1 point

18) What is the angular speed of a car rounding a circular turn of radius 110 m at 52.4 km/h

1 point

19) the ratio of angular velocities of the hour hand and minute hand of a watch is

2 points

1 : 1

720 : 1

43200 : 1

1 : 12

none of these

20) The angular momentum of a body about a fixed point is conserved if its velocity

1 point

increases

decreases

remains constant

none of these

21) the spin angular momentum and orbital angular momentum are usually differentiated in terms of

1 point

mass of the body

direction of the body

all of these

22) The value of g at the center of earth is

1 point

maximum

minimum

9.8 m/s^2

zero

23) If a rigid body is moving in a circular path about a fixed axis, then all the points on a rigid body have the same

1 point

angular displacement

agular speed

angular accelerration

all of these

24) When the angular velocity of a body decreases the direction of angular acceleration becomes ----- to velocity

1 point

parallel

opposite

arbitrary

none of these

25) Which of the following quantities remains the same in a planetary motion w.r.t sun?

2 points

Speed

Kinetic energy

Angular momentum

Angular speed

26) Angular acceleration is produced due to

1 point

Centripetal force

Torque

Force

both and b

all of these

27) The value of angular momentum is maximum if angle is equal to

1 point

0 degree

45 degree

90 degree

180 degree

28) torque per unit moment of inertia is equal to.

1 point

angular veloity

angular acceleration

inertia